The world needs new energy sources or and new materials for use in fuel cells, nanoelectronic devices or in pollution clean-up. Protein nanowires from Geobacter bacteria exhibit conductive properties and may be adapted for a variety of uses. However, growth of Geobacter needs to proceed under anaerobic conditions, because oxygen poisons the bacteria and inhibits grow. The native Geobacter bacteria also produce a limited number of nanowires per cell, which limits the nanowire yield during purification.